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Re: [Scheme-reports] More NaN and Infsanity
On Sat, Apr 28, 2012 at 04:49:24PM -0400, John Cowan wrote:
> > What should the value of the various trig functions be given nan/inf
> > values?
> Whatever IEEE 754 says. Editorial ticket #365 will add more examples
> (probably ripped off from R6RS) for the transcendental functions.
What about (rationalize x y) where x or y are nan or inf?
The notation seems to indicate that nan is allowed, since it's
"real but not rational". However, that same sentence seems to
indicate that rationalizing NaN would be an error.
On the other hand, R6RS seems to indicate that rationalize is
allowed to return +nan.0, see its examples:
(rationalize +inf.0 3) => +inf.0
(rationalize +inf.0 +inf.0) => +nan.0
(rationalize 3 +inf.0) => 0.0
I'm not sure if this is correct. OTOH, I don't fully grok
what rationalize does, so maybe I'm just wasting everyone's
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